﻿note：downloadAfterSpreadneedput into asystemDirectoryofExtendThe same location of the directory.

Extendtable of ContentsforSystem extensions directory(coreVersion does not contain anySpread)，childtable of Contentsstructurefor：

|-Action	Controller extension
|-Behavior	Behavior extension
|-Driver	Drive Expansion
|  ├Driver/Cache		Cache Drives
|  ├Driver/Db		Database-driven
|  ├Driver/Session	SESSIONdrive
|  ├Driver/TagLib	Tag library drive
|  ├Driver/Template	Template engine driver
|
|-Engine	Engine Expansion
|-Function	Extended Functions
|-Library	Library expansion
|  ├ORG	ORGClass Librarypackage
|  ├COM	COMClass Librarypackage
|
|-Mode	Extended mode
|-Model	Model extensions
|-Tool	Other extensions or tools
|-Vendor	Third-party libraries directory

onSpreadofdetaileduse，Please refer toDevelopmanualofSpreadchapter。